2010 · Q21
The remainder on dividing given integers a and b by 7 are respectively 5 and 4. What is the remainder when ab is divided by 7 ?
Elementary MathematicsNumber System
- A3
- B4
- C5
- D6
Explanation
ab ≡ 5×4 = 20 ≡ 6 (mod 7).
The remainder on dividing given integers a and b by 7 are respectively 5 and 4. What is the remainder when ab is divided by 7 ?
Explanation
ab ≡ 5×4 = 20 ≡ 6 (mod 7).